1. Field of the Invention
The present invention relates generally to an inner sole board, and more specifically to a customizable inner sole board.
2. Description of Related Art
Generally, soles and sole portions may be designed to provide support and protection, prevent injury, and correct or mitigate foot and other bodily ailments. Articles of footwear, for example, athletic shoes, may be designed to have soles or sole portions of varying flexibility to provide the support typically needed for a particular activity or sport. For example, soccer cleats are typically rigid in the posterior and more flexible in the forefoot region. However, football cleats tend to be more rigid in the forefoot region, in part to prevent turf toe injuries.
Different sole structures have been proposed. U.S. Pat. No. 3,444,586 to Dubner teaches a shoe made with a quick setting material that may be injected into the shoe to increase foot comfort. The Dubner shoe has an upper flexible portion, a sole, a heel, a sock lining, and a shank. The shank and sole have an opening through which molding material may be injected into the shoe. The sole interior includes four recesses and each recess accommodates a molding material receiving bag. The four receiving bags are in fluid communication with the opening and receive molding material upon injection. An injection means, including an injection gun, engages with the shoe at the opening to fill two receiving bags at a time. The material in two of the bags are filled and set while the wearer is sitting, and the material in the remaining two bags are filled and set while the wearer is walking.
U.S. Patent Application Number 2006/0242860 to Canvin teaches a thick insole with cavities able to receive inserts so that the hardness of the heel, arch, and metatarsal regions can be customized for a particular wearer. The insole has a main body with a bottom side having two cavities. A first cavity, the metatarsal cavity, mates with a metatarsal insert. A second cavity, the heel and arch cavity, mates with a heel and arch insert. The main body and inserts are separately made and comprise injection-molded foam. In order to provide variations in the hardness of the insole, the inserts may be formed of a different material than the main body. An article of footwear may be sold as a kit with multiple sets of interchangeable insoles. Each set of insoles is sized for the footwear and varies with respect to the durometer of the inserts or the durometer main body. The shape and size of portions of the insole may also be varied.
UK Patent Application GB2136671A to Buller teaches an injection molded insole having increased flexibility in the forepart. The insole has a forepart, a waist region, and a rear region. Generally, the insole is integrally formed through an injection molding process. The forepart is relatively thin and includes an aperture. As a result, the forepart is more flexible than the remainder of the insole. The portion of the forepart surrounding the aperture is the peripheral zone. In another embodiment, the aperture may be covered by a thin web of material. The insole, including the aperture or the web, is injection molded using one mold. In other embodiments, the aperture may be occupied by a filler comprising a foam plastic material. The filler is either formed and inserted into the aperture after the injection molding process or added into the mold before the injection molding process so that the filler bonds to the mold material during the molding process.
In general, footwear having soles with varying flexibility characteristics are known in the art. Soles using multiple materials are also generally known. However, the flexibility characteristics of these soles generally cannot be controlled when multiple materials are injected into a single mold. In particular, controlling the size and shape of at least one of the co-molded materials during the co-molding process is not known. Therefore, there is a need in the art for a system and method that addresses the shortcomings of the art.